Many MPs taking part in the debate yesterday were born before 1967, when being gay was still illegal.

In highly personal speeches some told of their struggles with their sexuality as they encouraged their colleagues to vote in favour of same-sex marriage.

Tory Crispin Blunt, said the Bill was part of an "astonishing and wonderful change" that had taken place over the past 50 years which had "taken millions of us from criminalisation to legal equality and the enjoyment of self-worth and validation".

"Those sentiments were certainly not apparent to me as a young man," he said. "I thought there was something wrong with me that had to be mastered, and for three decades I managed that struggle."

"The relief and happiness that comes from not having to do so any longer is due to the courage of others who fought for all the measures to advance equality over the past five decades that are the precursors to today’s Bill."

Stewart Andrew, the Conservative MP for Pudsey, told the Commons of the "personal battles" he had faced during "some of the most troubling and dark times" in his life.

"Many people have spoken and written about deeply held religious beliefs. From an early age, I developed those beliefs, going to church without the support of my family. That faith grew over time, but in my adolescence, I began to realise that I was gay.

He added to laughter: "Being gay in a small Welsh village really was like being the only gay in the village."

"It was the start of some very deep questioning about my faith and my sexuality that has taken me years to try to resolve, and I am still seeking answers."

Mike Freer, the MP who holds Finchley and Golders Green, once Margaret Thatcher's seat, challenged the idea he should be content with his civil partnership as it afforded him the same legal protections as marriage.

"I ask my married colleagues: did they get married for the legal protections it afforded them? Did they go down on one knee and say, 'Darling, please give me the protections marriage affords us'? Of course they did not," he said.

"My civil partnership was our way of saying to my friends and my family that this is who I love, this is who I am and this is who I want to spend the rest of my life with. I am not asking for special treatment; I am simply asking for equal treatment."

Bristol West Lib Dem Stephen Williams, noted he was born in 1966, when homosexuality was a criminal offence.

"During my life we have seen much progress, but it has come in fits and starts and has not always been easy," he said.

"Throughout my teenage years and my years at university, being openly gay was virtually impossible, because occasionally it could be a terrifying identity for an individual to have.

"I am thinking of the abuse that I received myself, and the far worse that I saw meted out to other people at school and university.

"What I say to colleagues on both sides of the House who oppose what we are trying to achieve today is please have some empathy with what your fellow citizens have been through. Equality is not something that can be delivered partially—equality is absolute."

Stourbridge Conservative Margot James, a vice chairman of the party, said being treated equally was "very welcome indeed".

"We still have some way to go, not just for gay people but in other areas too. My party should never flinch from the requirement to continue this progression; otherwise we may end up like the Republican party, which lost an election last year that it could have won were it not for its socially conservative agenda."

James added: "One last point that has not been raised is that gay people have always been allowed to marry—as long as they choose someone of the opposite sex.

"This has been the case in politics and in Hollywood for reasons that are well known. Many gay people today appreciate civil partnerships, but want more—they want the status of marriage. I am thinking particularly of younger gay people, who did not have to grow up in the environment that some of us had to grow up in. I support their right to declare their love in a state of marriage."

St Austell & Newquay Lib Dem Stephen Gilbert said he grew up "20-odd years ago in an environment that made it hugely difficult for me to be open, honest and up-front with my family, friends and workmates about the choices I wanted to take in life and the people I wanted to see".

"That was unacceptable 20-odd years ago and it is unacceptable today, but it remains the case for many hundreds of thousands of people across our country," he said.

"I welcome this historic Bill, which I think will end a form of discrimination and, perhaps more crucially, send a signal that this House values everybody equally across our country.

"That signal will deeply affect people like me in the same way as I was affected 20 years ago, when I saw this House vote to equalise the age of consent. That was the first time I saw other gay people on a TV screen and it was the first time that I realised that I was not alone. It changed my life."

Former Conservative police minister, Nick Herbert, who toured TV studios on the day of the debate making the case for gay mariage was also born before being gay was decriminalised.

"Not so long ago, it was possible to sack someone because they were gay," he said. "People did not dare to be open."

"Thank goodness so much has changed in my lifetime. That progress should be celebrated, but we should not believe that the journey is complete.

"I think of the gay children who are still bullied at school or who are fearful about whether their friends and families accept them.

"I think of sportsmen and women—vital role models—who still do not feel able to come out. The signal we send today about whether the law fully recognises the place of gay people in our society will really matter."